Dbiving unit and controlling mechanism for cranes and the like



| D. NILSON 1,790,281

DRIVING UNIT AND CONTROLLING MECHQNISM FOR CRANES AND THE LIKE Jan. 27, 1931.

Filed June 11, 1927 Patented Jan. 27, 1931 UNITED STATES OFFICE c LEONARD n. NILsON, or WAYZATA, MINNnsoTA. Ass cNoa ro nanounrrn Manufac- TUBING COMPANY, or s'r. PAUL, MINNESOTA DRIVING um 4ND CONTROLLING mEcHAN'I'sm' roR cams ANnm'LIxE Application filed June 11,

The object of my invention is to provide a driving device in the form of a unitary structure to be attached to the frame of a crane or thelike for the purpose of driving a drum shaft on the crane, the parts of such device being comparatively simple, durable andinexpensive to manufacture.

A further object of my invention is to provide such a unit especially adapted for use inautomobile service Wrecking cars and ineluding an electric motor which can be driven from the storage battery usually furnished as standardequipment for such cars.

Another object of my present invent-ion is to provide for the handling of comparatively large loads with a small motor such as the starting motor of an automobile.

Still another object is to provide novel control mechanism for the motor which is normally maintained in a neutral position but which can be moved to either of two positions for energizing the motor and causing itto be rotated in either direction desired.

More particularly it is my object to provide such control mechanism in the form of a double pole double throw switch so connected to the motor itself that when the switch is thrown in one direction the motor will berotated in one direction and when thrown in an opposite direction, the motor will'be rotated in an opposite direction.

Still a further object is to provide two pairs or sets of brushes for the armature of a four pole motor whereby the armature of themotor will rotate in one direction when one set of brushes is energized and will rotate in the opposite directionwhen the other set is energized.

With these and other objects in view, my invention consists in the construction, arrangement and combination of thevarious parts of my driving unit and controlling mechanism for cranes,-whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in theaccompanying drawings, in which:

Figure 1 is an elevation illustratingmy 'driving unit in operativeconnection with a 1927. Serial No; 198,279.

gear and showing parts broken away and 2 mutator cover for the driving motor showing my control switch mounted thereon.

igure: 4 is a sectional view taken on the line 4-4 of Figure 1 illustrating the setsof brushes of my control device and their relation to the commutator and Figure 5 is a diagrammatical view of the electric circuit employed in the use of my unit and diagrammatically illustrates the control rod'of my device. Y I

On the accompanying. drawings I have used the reference numeral 44 to indicate a portion of agear housing orthe like to which my drivingunit may be secured. A cover 52 is provided therefor.

.Formed' inthe plate 44 is an opening 7 6. A spacer disc 7 8'having a positioning flange 80 coacting with the opening 7 6 is positioned against the housing 44. The spacer disc 78 is provided withan annular rabbet 81 adapted to receive'the casing of an-electric motor 82. The motor 82 is of the ordinary automobile starter type. These-motors are easy to obtain and are in generaluse and especially adaptedto be operated from the type of storage battery used for the purpose of starting. the engine of a wrecking car when the driving unit is used in connection with a wreckingcrane thereon.

The motor 82 is provided with a commutator' and brush cover 84 which is positioned over the end of the motor 82 and'rests against a shoulder 86$ A pair of stay bolts 88 extend through the cover84, through the shell of the motor 82, through the spacer disc 78 andare screw treaded into the plate 44 whereby the spacer disc 78, the motor 82 and the cover 84 are held assembled with relation to the plate 44 The shaft 90 of the motor extends through an opening 92 in the spacer disc 7 8 and into the casing formed by the plate 44 and the cover 52. An oil cup 94 is provided for lubrication of the shaft 90 at the point where it extends through the spacer disc 78. Secured to the end of the shaft 90 is a pinion 96 adapted to mesh with a gear 112, or other suitable means may be provided to drive a mechanism from the motor.

In a driving unit as I have described, it is desirable that a means of control such as a switch be provided for the motor 82. It is further desirable that such a control should be capable of reversing the motor 82 aswell as of starting and stopping it. To accomplish this desirable result, I provide an arrangement ofbrushes 140 and 142 adapted to contact with the commutator 136 of the motor 82. In conjunction with the brushes 140 and 142 I provide a switch mechanism inditcjated generally by the reference character 1 The brushes 140 and 142 are pivoted to pins 138 extending from the cover member 84 of the motor. Suitable resilient mechanism such as coil springs wrapped around the pins 138 may be provided for constraining thebrushes 140 and 142 toward the commutator 136. This brush construction is similar to brush constructions now in general use. y

The brushes 140 constitute one set (in this case a pair) and the brushes 142 constitute another set, either set of which can be energized with an electric current independent of the other whereby the armature of the motor (which is of the four pole type) 82 can be caused to rotate in either direction. For controlling the supply of current to the brushes 140 and 142, I provide the switch C.

The switch C comprises a pair of bifurcated posts 144 secured to the cover member 84. Pivotally mounted on the posts 144 is a pair of switch blades 146 of the knife type.

, The posts 144 are suitably insulated from the cover 84 to prevent transmission of electric current. V

Cross members 148 are provided for connecting the ends of the knife blades 146 together to form a unitary switch blade device adapted to be rocked on the pivot bolts extending through the posts 144. The members 148 are insulated from the knife blades whereby the blades are electrically independent of each other. For imparting such rocking movement to the blades 146 Iprovide a rod 150 extending through an opening 152 in one of the cross bars 148 and screwed into a screw threaded opening 154 in the other cross bar 148. V

An eye 156 is provided on one end of the rod 150, the purpose of which will hereinafter be described. Mounted on the cover member 84 and suitably insulated therefrom are two sets of contact members 158 and 160. The contact members just referred to, are formed of resilient material and provide expansible slots adapted to receive the knife blades 146. r

The contact members 158 are connected to the brushes 140 by lead wires 162 and the contact members 160 are connected to the brushes 142 by lead wires 164.

A switch cover 166 is provided for encasing the entire switch mechanism 0 and the cover member 84. The cover 166 is tubular and surrounds the cover'member 84 and is held in position thereon by screws 168 extending therethrough and screwed into the cover'84. 'A suitable closure cap 17 Die provided for the outer, open end of the cover member 166 and may be held in position'by cotter keys 172 as illustrated in Figure 3 of the drawings. The member 166 is provided with a slot 167 for the rod 150. I

A ground connection is provided for one of the posts 144 by connecting a clip 174 to such post and to'the cover member 166'by a terminal post 176. The other post 144 is connected by lead wires 17 8 to one end of each of the field coils 180 of the motor 82 and the other ends of these field coils are connected to a terminal post 182. r

In Figure 5 I have illustrated the connections just referred to in the circuit of en electric storage battery 184 whereby the current from the storage battery will flow to one side of the switch G, then to either set of brushes 140 or 142 depending on which'position the switch is moved to and then back to the other side of the switch. The current will then flow through the field coils 180 and back to c the storage battery 184. r I

I provide a convenient and easily accessible control device for the switch 0 in the form of a control rod 186 having an end 188 bent to extend through the eye 156 of the rod 150.

The rod 186 extends through an ear 190 on the plate 44 and is capable of sliding movement therethrough. The outer end of the rod 186 is provided with a knob 192 for the convenience of the operator. 7 v

Positioned on the rod 186 between the rod 192 and the ear 190 is a compression coil spring 194. 7 Another spring 196 is positioned on the rod 186 on the opposite side of'the ear 190 and extends from the ear to wardly for rocking the switch'blades 146 to cause the shaft 90 of the motor 82 to rotate in the desired direction.

It will be obvious from the foregoing that I have provided a unitary structure having a motor easily controlled for rotation in either 1 direction desired and which can be mounted on the frame of a wrecking crane or which may be used for any other suitable purpose.

An efiicient controlling switch is provided for operating myvdriving unit, the switch being mounted directly on the brush end of the motor itself so that short electrical connections may be made between the brushes and the switch. The knife blades of the switch operate in a position laterally with respect to the armature.

Although I have shown one embodiment of a driving unit in accordance with my invention, it is to be understood that mechanical equivalents can be substituted for the various parts thereof without departing from the real spirit and purpose of my invention and it is therefore my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. The combination with an electric motor having an end cap for covering the commutator thereof and a plurality of brushes mounted on one side of said cap, of a controlling device comprising contacts secured to the other side of said cap and electrically connected with said brushes, a rockable switch blade adapted to selectively coact with said contacts when rocked to different positions and spring balanced means to cause said switch blade to assume a neutral position.

2. The combination with an electric motor having an end cap for covering the commutator thereof and a plurality of brushes mounted on one side of said cap, of a controlling device comprising contacts secured to the other side of said cap and electrically connected with said brushes, and a rockable switch blade adapted to selectively coact with said contacts when rocked to different positions.

3. The combination with an electric motor having an end cap for covering the commutator thereof, and a plurality of brushes mounted on one side of said cap, of a controlling device comprising contacts secured to the other side of said cap and electrically connected with said brushes, a rockable switch blade adapted to selectively coact with said cont-acts when rocked to different positions, and spring balanced means to cause said switch blade to assume a neutral position, said last means comprising a rod slidably mounted through a stationary member and spring encircling said rod and arranged on each side of said stationary member.

Des Moines, Iowa, May 27 1927.

LEONARD D. NILSON. 

